3D Printing A Prosthetic-Compatible Golf Club

September 2, 2022 by Danie Conradie No comments

Relearning an old sport, or starting a new one, can be challenging for amputees. Besides the obvious physical aspects, custom prosthetics or adaptors might need to be made and fitted, which can be very expensive. With the power of 3D printing and some machining, [Ian Davis] was able to build a custom prosthetic golf club to get a quadruple amputee back on the greens.

The recipient of this prosthetic lost both hands above the wrists, so [Ian] had to come up with a mechanism that could hold the club and mimic wrist motion throughout the swing. He was able to achieve this motion with a simple four-plate hinge for each arm. For optimal ergonomics, [Ian] also added two-axis adjustability, with only a single bolt needing to be loosened per axis. A standard golf club can be used and is clamped in the printed holders.

Machined prosthetic sockets were used to allow quick connection to the user’s existing prosthetic forearms. Theoretically, this should also allow him to switch clubs without excessive hassle. [Ian], an amputee himself, has used his engineering skills to build a series of prosthetic hands and even a custom controller mod to get back to gaming with fewer flesh fingers.

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Presence-Detecting Cushion Keeps You From Sitting Your Life Away

August 11, 2022 by Dan Maloney 13 Comments

They say that sitting is the new smoking. They’re wrong — smoking is much, much worse, for you than sitting, and smoking only while standing or while jogging around the block in no way to justify the habit. But they’re also not wrong that humans weren’t made for extended periods parked on their posteriors, but we do it anyway, to the detriment of our heart health, posture, and general well-being. So something like this butt-detecting stand-up reminder could make a big difference to your health.

While like many of us, [Dave Bennett] has a wearable that prompts him to get up and move around after detecting 30 minutes of sitting, he found that it’s too easy to dismiss the alarm and just go right on sitting. Feeling like he needed a little more encouragement to get up and go, he built a presence detector completely from scratch. His sensor is a sheet of static-protective Velostat foam wrapped in conductive tape; when compressed, the resistance across the pad drops, making it easy to detect with a simple comparator circuit.

We admit to getting excited when we first saw the alarm circuit; a quick glance at the schematic seemed like it was based on a 555, which it totally could be. But no, [Dave]’s design goals include protection against spoofing the alarm with a quick “cheek sneak,” which was most easily implemented in code. So that 8-pin device in the circuit is an ATtiny85, which sounds the alarm after 30 minutes and requires him to stay off his butt for a full minute before resetting. The video below hits the high points of design and shows it in use.

Annoying? Yes, but that’s the point. Of course a standing desk would do the same thing, but that’s not going to work for everyone, so this is a nice alternative.

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Cool Face Mask Turns Into Over-Engineered Headache

July 31, 2022 by Ryan Flowers 13 Comments

Seeing his wife try to use a cool face mask to get through the pain of a migraine headache, [Sparks and Code] started thinking of ways to improve the situation. The desire to save her from these debilitating bouts of pain drove him to make an actively cooled mask, all the while creating his own headache of an over-engineered mess.

Void spaces inside the printed mask are filled with chilled water.

Instead of having to put the face mask into the refrigerator to get it cold, [Sparks and Code] wanted to build a mask that he could circulate chilled water through. With a large enough ice-filled reservoir, he figured the mask should be able to stay at a soothing temperature for hours, reducing the need for trips to the fridge.

[Sparks and Code] started out by using photogrammetry to get a 3D model of his wife’s face. Lack of a compatible computer and CUDA-enabled GPU meant using Google Cloud to do the heavy lifting. When they started making the face mask, things got complicated. And then came the unnecessary electronics. Then the overly complicated and completely unnecessary instrumentation. The… genetic algorithms? Yes. Those too.

We won’t spoil the ending — but suffice it to say, [Sparks and Code] learned a cold, hard lesson: simpler is better! Then again, sometimes being over-complicated is kind of the point such as in this way-too-complex gumball machine.

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Electrolytes, They’re What Dehydrated Hackaday Writers Crave!

July 27, 2022 by Jenny List 106 Comments

The oddly prophetic 2006 comedy film Idiocracy features an isotonic drink called Brawndo, whose marketing continuously refers to its electrolytes as a miraculous property. Brawndo is revealed in the film to be useless for agricultural irrigation, but yesterday perhaps a couple of Hackaday writers could have used a bottle or two. At the MCH hacker camp, the record heat of a Dutch summer under the influence of global warming caused us to become dehydrated, and thus necessitated a trip to the first aid post for some treatment. We’d done all the right things, staying in the shade, keeping as cool as we could, eating salty foods like crisps, and drinking plenty of liquids, so what had gone wrong?

Perhaps Club-Mate Should Have An Isotonic Version

The answer will probably be obvious to trained observers, we’d become deficient in those electrolytes. Our bodily stocks of sodium and potassium salts had become exhausted by sweat and all that extra water requiring trips to the toilet, so while we weren’t dehydrated in liquid terms we had exhausted some of the essentials to our cellular function.

The symptoms would have been easy to spot given the right training, but at a hacker camp it was too easy to attribute a headache and tiredness to a late night. For me the point at which it became obvious something was significantly wrong came when my thought processes started to slow down and my movement became a lot less easy. I’m a long-distance walker and cyclist, yet here I was walking like an octogenarian. If I’d know what to spot I might also have noticed that I had stopped sweating despite the heat. I found a friend (Thanks Gasman!), and together we made our way to the first aid post. MCH2022 first aiders were very efficient, and I was given a cup of oral rehydration salts which restored me to health in a matter of minutes. Continue reading “Electrolytes, They’re What Dehydrated Hackaday Writers Crave!” →

3D Printed Splint Goes Toe To Toe With Medical Grade Equipment

July 6, 2022 by Ryan Flowers 11 Comments

When you think of medical devices, the idea of high end, well, pretty much everything, comes to mind. This is definitely the case when it comes to prosthetics, or in this similar case, custom fit splints. A hacker by the name of [sammyizimmy] wasn’t put off by the complexity of a custom splint for his fractured big toe, and a great hack made it all possible.

InVesalius reconstructs the CT Scan imagery

The story starts with a fractured toe, and an open source project called InVesalius. Instead of doing an X-Ray on his toe, [sammyizimmy]’s doctor decided to do a Computed Tomography scan (aka CT Scan) to get a look at the damage. For being as ubiquitous as they are, it’s easy to forget that a CT scan is an extremely detailed look at both internal and external parts.

The hack really began when [sammyizimmy] asked his radiologist for a copy of the CT Scan. This is something most radiologists will provide upon request, although many people don’t know you can even ask. [sammyizimmy] took his CT scan and opened it up in InVesalius, and then reconstructed the skin layer only, and then… head over to the “3d printed Toe Splint” page at Hackaday.io for the rest!

If medical hacks are are your kind of medicine, you might appreciate this HDD-Turned-Centrifuge too!

A Sleep Monitor For Minimum Outlay

June 15, 2022 by Jenny List 9 Comments

There are a variety of instruments used in sleep studies to measure bodily activity during sleep and consequent sleep quality. Many of them use techniques that perhaps aren’t so easy to replicate on the bench, but an EEG or electroencephalograph to measure brain waves can be achieved using a readily-available module. [Ben Jabituya] shows us a sleep monitor using one of these modules, an EGG Mikroe Click.

The brains of the operation is an Adafruit Adalogger Feather M0, which is hooked up to a headband containing the sensing electrodes. The write-up gives us a round-up of the available boards, which should be handy for any experimenters in this field. The firmware meanwhile was written using the Arduino IDE. It collects raw sampling data to an SD card, and one surprise comes in just how relatively small a space it requires to store a night’s results.

Finally, a Python script was used to process the data and turn it into a spectrogram to look at brain activity through the night. He envisages using the device for triggering lucid dreaming during REM sleep, but we can see it might be rather useful for sleep disorder sufferers, too. Take a look at it in the video below the break. Continue reading “A Sleep Monitor For Minimum Outlay” →

Live Glucose Monitoring With The Apple Watch

June 6, 2022 by Al Williams 27 Comments

There has been a rumor that Apple is working on a glucose monitoring solution for the Apple watch. [Harley] decided not to wait and managed to interface an Abbot FreeStyle Libre sensor with the Apple watch. The sensor doesn’t directly read glucose continuously, but it does allow for more frequent reading which can help diabetic patients manage their blood sugar levels. However, as part of the hack, [Harley] effectively converts the meter to a continuous-reading device, another bonus.

The trick is to add a Bluetooth transmitter to the NFC sensor. Using a device called a MiaoMiao, the task seems pretty simple. The MiaoMaio is small, waterproof, and lasts two weeks on a charge, which is longer than the sensor’s life. Honestly, this is the hack since once you have the data flowing over Bluetooth, you can process it in any number of ways including using an app on the Apple watch.

It isn’t perfect. There’s a slight lag with readings due to the way the sensor works. However, you usually don’t care as much about the absolute value of your glucose (unless it is very high or very low). You are usually more interested in the slope of the change. This data is more than good enough for that.

In fact, the most complex part of this seems to be the watch app. It might be less work to feed the data to a machine learning model and let AI guide your insulin injections. Something to think about.

We have a keen interest in glucose monitoring around here and we know why it is so darn hard. Honestly, the idea of pushing glucose meter data to a watch isn’t new, but this is a well-done implementation with a lot of possibilities.